The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 21, 1989
Filed:
Apr. 28, 1987
Daniel A Spielman, Philadelphia, PA (US);
Other;
Abstract
A device for monitoring the relative point of impact of an object in flight proximal a reference line on a surface. The reference line may be imaginary or it may be visually perceptible. In a preferred application, the reference line is the outer edge of a game court boundary stripe such as the service box stripe or the base line stripe on a tennis court. At least one plane of radiated energy, preferably light beams, is pre-positioned with respect to the reference line. Detectors, preferably photodetectors, provide data signals indicative of the relative elevation of the object at two successive points in time based on intersection of at least one plane of radiated energy by the object. A programmed microcomputer determines whether the point of surface impact is to one side or another of the reference line, or coincident with the reference line, based on the data signals. The microcomputer commands an annunciator to provide an audible or visual indication of the determination.